Exposure to asbestos is the predominant cause of pleural mesothelioma (PM). The PM is a tumor difficult to diagnose, chemoresistant, and with rising Incidence. The long latency periods and the lack of preventive and therapeutic strategies for the MP, suggest that asbestos will be a social and health issue in the near future. Therefore, this overview focuses on current knowledge of epigenetic alterations and on the key role of microRNAs, small RNAs that negatively regulate gene expression, as biomarkers in PM development. Dysregulated microRNA expression pattern is specific for different cancers, including MP. MicroRNA expression analysis is a promising tool for diagnosis, typing of MP than normal tissue and other lung tumors and monitoring of new therapies. However, a better knowledge of miRNA signatures in PM is still necessary to verify the contribution of specific miRNAs as diagnostic biomarkers, also compared to different asbestos forms, exposure and subject work history.